Date: Fri, 23 Sep 2011 02:48:30 GMT From: Ben Morrow <ben@morrow.me.uk> To: freebsd-gnats-submit@FreeBSD.org Subject: ports/160930: [PATCH] devel/gdb: HW watchpoint support for amd64 Message-ID: <201109230248.p8N2mUwS084986@red.freebsd.org> Resent-Message-ID: <201109230250.p8N2o3B3031492@freefall.freebsd.org>
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>Number: 160930
>Category: ports
>Synopsis: [PATCH] devel/gdb: HW watchpoint support for amd64
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-ports-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Fri Sep 23 02:50:03 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator: Ben Morrow
>Release: 8.2-RELEASE-p2
>Organization:
>Environment:
FreeBSD anubis.morrow.me.uk 8.2-RELEASE-p2 FreeBSD 8.2-RELEASE-p2 #7: Thu Jun 9 14:58:42 BST 2011 mauzo@anubis:/usr/obj/usr/src/sys/ANUBIS amd64
>Description:
Currently gdb on amd64 has no support for hardware watchpoints. Since
the hardware does actually support them, this is a little irritating.
>How-To-Repeat:
Set a watchpoint in gdb72 on amd64. It will be a software watchpoint,
and the program being debugged will run extremely slowly.
>Fix:
The attached patch adds support.
Patch attached with submission follows:
diff -Naur devel/gdb.orig/Makefile devel/gdb/Makefile
--- devel/gdb.orig/Makefile 2011-02-25 07:50:35.000000000 +0000
+++ devel/gdb/Makefile 2011-09-23 01:43:15.375784434 +0100
@@ -84,6 +84,7 @@
@${REINPLACE_CMD} -e 's/$$/ [GDB v${PORTVERSION} for FreeBSD]/' \
${WRKSRC}/gdb/version.in
@${CP} ${FILESDIR}/fbsd-threads.c ${WRKSRC}/gdb
+ @${CP} ${FILESDIR}/amd64bsd-nat.h ${WRKSRC}/gdb
do-install:
${INSTALL_PROGRAM} ${WRKSRC}/gdb/gdb ${PREFIX}/bin/gdb${VER}
diff -Naur devel/gdb.orig/files/amd64bsd-nat.h devel/gdb/files/amd64bsd-nat.h
--- devel/gdb.orig/files/amd64bsd-nat.h 1970-01-01 01:00:00.000000000 +0100
+++ devel/gdb/files/amd64bsd-nat.h 2011-09-23 01:39:50.852195530 +0100
@@ -0,0 +1,38 @@
+/* Native-dependent code for amd64 BSD's.
+
+ Copyright (C) 2011 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef AMD64BSD_NAT_H
+#define AMD64BSD_NAT_H
+
+/* Create a prototype *BSD/amd64 target. The client can override it
+ with local methods. */
+
+extern struct target_ops *amd64bsd_target (void);
+
+/* low level amd64 debug register functions used in amd64fbsd-nat.c. */
+
+extern void amd64bsd_dr_set_control (unsigned long control);
+
+extern void amd64bsd_dr_set_addr (int regnum, CORE_ADDR addr);
+
+extern void amd64bsd_dr_reset_addr (int regnum);
+
+extern unsigned long amd64bsd_dr_get_status (void);
+
+#endif /* amd64bsd-nat.h */
diff -Naur devel/gdb.orig/files/patch-gdb-Makefile.in devel/gdb/files/patch-gdb-Makefile.in
--- devel/gdb.orig/files/patch-gdb-Makefile.in 2010-11-16 20:39:48.000000000 +0000
+++ devel/gdb/files/patch-gdb-Makefile.in 2011-09-23 01:41:43.239509675 +0100
@@ -1,6 +1,6 @@
---- gdb/Makefile.in.orig 2010-02-02 18:16:53.000000000 -0500
-+++ gdb/Makefile.in 2010-10-13 16:09:43.312803000 -0400
-@@ -524,7 +524,7 @@
+--- gdb/Makefile.in.orig 2010-08-19 19:40:34.000000000 +0100
++++ gdb/Makefile.in 2011-09-23 01:31:58.825043698 +0100
+@@ -546,7 +546,7 @@
xstormy16-tdep.o \
xtensa-config.o xtensa-tdep.o xtensa-linux-tdep.o \
glibc-tdep.o \
@@ -9,7 +9,16 @@
nbsd-tdep.o obsd-tdep.o \
sol2-tdep.o \
solib-frv.o solib-irix.o solib-svr4.o solib-target.o \
-@@ -720,7 +720,7 @@
+@@ -731,7 +731,7 @@
+ osf-share/cma_deb_core.h osf-share/AT386/cma_thread_io.h \
+ osf-share/cma_sched.h proc-utils.h arm-tdep.h ax-gdb.h ppcnbsd-tdep.h \
+ cli-out.h gdb_expat.h breakpoint.h infcall.h obsd-tdep.h \
+-exec.h m32r-tdep.h osabi.h gdbcore.h solib-som.h \
++exec.h m32r-tdep.h osabi.h gdbcore.h solib-som.h amd64bsd-nat.h \
+ i386bsd-nat.h xml-support.h xml-tdesc.h alphabsd-tdep.h gdb_obstack.h \
+ ia64-tdep.h ada-lang.h varobj.h frv-tdep.h nto-tdep.h serial.h \
+ c-lang.h d-lang.h frame.h event-loop.h block.h cli/cli-setshow.h \
+@@ -744,7 +744,7 @@
gdbserver/linux-low.h gdbserver/gdb_proc_service.h \
gdbserver/regcache.h gdbthread.h dwarf2-frame.h nbsd-nat.h dcache.h \
amd64-nat.h s390-tdep.h arm-linux-tdep.h exceptions.h macroscope.h \
@@ -18,7 +27,7 @@
mdebugread.h m88k-tdep.h stabsread.h hppa-linux-offsets.h linux-fork.h \
ser-unix.h scm-lang.h inf-ptrace.h terminal.h ui-out.h frame-base.h \
f-lang.h dwarf2loc.h value.h sparc-tdep.h defs.h target-descriptions.h \
-@@ -1130,7 +1130,7 @@
+@@ -1161,7 +1161,7 @@
# Removing the old gdb first works better if it is running, at least on SunOS.
gdb$(EXEEXT): gdb.o libgdb.a $(ADD_DEPS) $(CDEPS) $(TDEPLIBS)
rm -f gdb$(EXEEXT)
@@ -27,8 +36,8 @@
-o gdb$(EXEEXT) gdb.o libgdb.a \
$(TDEPLIBS) $(TUI_LIBRARY) $(CLIBS) $(LOADLIBES)
-@@ -1402,7 +1402,7 @@
- arm-linux-nat.c arm-linux-tdep.c arm-tdep.c \
+@@ -1433,7 +1433,7 @@
+ arm-linux-nat.c arm-linux-tdep.c arm-symbian-tdep.c arm-tdep.c \
armnbsd-nat.c armbsd-tdep.c armnbsd-tdep.c armobsd-tdep.c \
avr-tdep.c \
- bsd-uthread.c bsd-kvm.c \
diff -Naur devel/gdb.orig/files/patch-gdb-amd64-nat.h devel/gdb/files/patch-gdb-amd64-nat.h
--- devel/gdb.orig/files/patch-gdb-amd64-nat.h 1970-01-01 01:00:00.000000000 +0100
+++ devel/gdb/files/patch-gdb-amd64-nat.h 2011-09-23 01:41:07.842903111 +0100
@@ -0,0 +1,12 @@
+--- gdb/amd64-nat.h.orig 2011-09-23 01:36:54.874780473 +0100
++++ gdb/amd64-nat.h 2011-09-23 01:28:46.964218514 +0100
+@@ -50,9 +50,4 @@
+ extern void amd64_collect_native_gregset (const struct regcache *regcache,
+ void *gregs, int regnum);
+
+-/* Create a prototype *BSD/amd64 target. The client can override it
+- with local methods. */
+-
+-extern struct target_ops *amd64bsd_target (void);
+-
+ #endif /* amd64-nat.h */
diff -Naur devel/gdb.orig/files/patch-gdb-amd64bsd-nat.c devel/gdb/files/patch-gdb-amd64bsd-nat.c
--- devel/gdb.orig/files/patch-gdb-amd64bsd-nat.c 1970-01-01 01:00:00.000000000 +0100
+++ devel/gdb/files/patch-gdb-amd64bsd-nat.c 2011-09-23 01:40:24.590895157 +0100
@@ -0,0 +1,91 @@
+--- gdb/amd64bsd-nat.c.orig 2011-09-23 01:35:24.211306143 +0100
++++ gdb/amd64bsd-nat.c 2011-09-23 01:28:28.444487431 +0100
+@@ -33,6 +33,7 @@
+
+ #include "amd64-tdep.h"
+ #include "amd64-nat.h"
++#include "amd64bsd-nat.h"
+ #include "inf-ptrace.h"
+
+
+@@ -126,3 +127,80 @@
+ t->to_store_registers = amd64bsd_store_inferior_registers;
+ return t;
+ }
++
++
++/* Support for debug registers. */
++
++#ifdef HAVE_PT_GETDBREGS
++
++/* Not all versions of FreeBSD/i386 that support the debug registers
++ have this macro. */
++#ifndef DBREG_DRX
++#define DBREG_DRX(d, x) ((&d->dr0)[x])
++#endif
++
++static void
++amd64bsd_dr_set (int regnum, unsigned long value)
++{
++ struct dbreg dbregs;
++
++ if (ptrace (PT_GETDBREGS, PIDGET (inferior_ptid),
++ (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
++ perror_with_name (_("Couldn't get debug registers"));
++
++ /* For some mysterious reason, some of the reserved bits in the
++ debug control register get set. Mask these off, otherwise the
++ ptrace call below will fail. */
++ DBREG_DRX ((&dbregs), 7) &= ~(0x0000fc00);
++
++ DBREG_DRX ((&dbregs), regnum) = value;
++
++ if (ptrace (PT_SETDBREGS, PIDGET (inferior_ptid),
++ (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
++ perror_with_name (_("Couldn't write debug registers"));
++}
++
++void
++amd64bsd_dr_set_control (unsigned long control)
++{
++ amd64bsd_dr_set (7, control);
++}
++
++void
++amd64bsd_dr_set_addr (int regnum, CORE_ADDR addr)
++{
++ gdb_assert (regnum >= 0 && regnum <= 4);
++
++ amd64bsd_dr_set (regnum, addr);
++}
++
++void
++amd64bsd_dr_reset_addr (int regnum)
++{
++ gdb_assert (regnum >= 0 && regnum <= 4);
++
++ amd64bsd_dr_set (regnum, 0);
++}
++
++unsigned long
++amd64bsd_dr_get_status (void)
++{
++ struct dbreg dbregs;
++
++ /* FIXME: kettenis/2001-03-31: Calling perror_with_name if the
++ ptrace call fails breaks debugging remote targets. The correct
++ way to fix this is to add the hardware breakpoint and watchpoint
++ stuff to the target vector. For now, just return zero if the
++ ptrace call fails. */
++ if (ptrace (PT_GETDBREGS, PIDGET (inferior_ptid),
++ (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
++#if 0
++ perror_with_name (_("Couldn't read debug registers"));
++#else
++ return 0;
++#endif
++
++ return DBREG_DRX ((&dbregs), 6);
++}
++
++#endif /* PT_GETDBREGS */
diff -Naur devel/gdb.orig/files/patch-gdb-amd64fbsd-nat.c devel/gdb/files/patch-gdb-amd64fbsd-nat.c
--- devel/gdb.orig/files/patch-gdb-amd64fbsd-nat.c 2010-11-16 20:39:48.000000000 +0000
+++ devel/gdb/files/patch-gdb-amd64fbsd-nat.c 2011-09-23 03:09:20.209594449 +0100
@@ -1,5 +1,5 @@
---- gdb/amd64fbsd-nat.c.orig 2010-10-13 14:53:14.425152000 -0400
-+++ gdb/amd64fbsd-nat.c 2010-10-13 15:15:01.080198000 -0400
+--- gdb/amd64fbsd-nat.c.orig 2010-02-03 15:30:25.000000000 +0000
++++ gdb/amd64fbsd-nat.c 2011-09-23 03:08:51.942111416 +0100
@@ -27,6 +27,7 @@
#include <signal.h>
#include <stddef.h>
@@ -8,7 +8,16 @@
#include <sys/ptrace.h>
#include <sys/sysctl.h>
#include <machine/reg.h>
-@@ -92,6 +93,47 @@
+@@ -34,6 +35,8 @@
+ #include "fbsd-nat.h"
+ #include "amd64-tdep.h"
+ #include "amd64-nat.h"
++#include "amd64bsd-nat.h"
++#include "i386-nat.h"
+
+
+ /* Offset in `struct reg' where MEMBER is stored. */
+@@ -92,6 +95,47 @@
};
@@ -56,3 +65,23 @@
/* Support for debugging kernel virtual memory images. */
#include <sys/types.h>
+@@ -155,6 +199,19 @@
+
+ /* Add some extra features to the common *BSD/i386 target. */
+ t = amd64bsd_target ();
++
++#ifdef HAVE_PT_GETDBREGS
++
++ i386_use_watchpoints (t);
++
++ i386_dr_low.set_control = amd64bsd_dr_set_control;
++ i386_dr_low.set_addr = amd64bsd_dr_set_addr;
++ i386_dr_low.reset_addr = amd64bsd_dr_reset_addr;
++ i386_dr_low.get_status = amd64bsd_dr_get_status;
++ i386_set_debug_register_length (8);
++
++#endif /* HAVE_PT_GETDBREGS */
++
+ t->to_pid_to_exec_file = fbsd_pid_to_exec_file;
+ t->to_find_memory_regions = fbsd_find_memory_regions;
+ t->to_make_corefile_notes = fbsd_make_corefile_notes;
diff -Naur devel/gdb.orig/files/patch-gdb-config-i386-fbsd64.mh devel/gdb/files/patch-gdb-config-i386-fbsd64.mh
--- devel/gdb.orig/files/patch-gdb-config-i386-fbsd64.mh 1970-01-01 01:00:00.000000000 +0100
+++ devel/gdb/files/patch-gdb-config-i386-fbsd64.mh 2011-09-23 03:16:21.204024239 +0100
@@ -0,0 +1,10 @@
+--- gdb/config/i386/fbsd64.mh.orig 2011-09-23 03:15:43.254648862 +0100
++++ gdb/config/i386/fbsd64.mh 2011-09-23 03:14:06.843804785 +0100
+@@ -1,6 +1,6 @@
+ # Host: FreeBSD/amd64
+ NATDEPFILES= fork-child.o inf-ptrace.o \
+- fbsd-nat.o amd64-nat.o amd64bsd-nat.o amd64fbsd-nat.o \
++ fbsd-nat.o i386-nat.o amd64-nat.o amd64bsd-nat.o amd64fbsd-nat.o \
+ bsd-kvm.o
+
+ LOADLIBES= -lkvm
>Release-Note:
>Audit-Trail:
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